At the present time, electrical power cords are generally connected to hand-held small appliances, such as hair dryers, by passing an electric cord through a resilient sleeve connected to the appliance. However, the sleeve allows for little or virtually no degree of movement in any direction. Thus, when the appliance is turned, the cord may become twisted or even knotted. It is an inconvenience to untangle the cord and a tangled cord may be unsightly. Additionally, twisting of the cord causes much stress and strain of the cord at the point where the cord exits the appliance body, thereby ultimately resulting in a break or split in the insulative outer body of the cord. Once the cord insulation is broken, the electrical wires contained therewithin may be exposed. This poses a high safety concern for the user. Accordingly, by preventing twisting of the cord, we are able to produce a product that is not only convenient, but also much safer and has a longer life.
It has been suggested, in a series of patents, that a commutator-brush type of electrical connection may be used to provide a rotative connector. This permits the appliance to be turned about one axis without twisting the power cord. However, it does not provide for any other movement.
U.S. Pat. No. 4,040,896 ('896 patent), entitled "Electric Device Having Rotary Current Collecting Means", is directed to a three part structure having an inner rotatable electrode carrier ("device body 5"or "first conductor carrier") and a housing ("device body 2").
U.S. Pat. No. 4,061,381 ('381 patent), entitled "Twist Prevention Device", relates to a rotatable cable connector. It shows two helically wound connectors forming a wire spring.
U.S. Pat. No. 3,937,543 ('543 patent), entitled "Electrical Swivel Contact Assembly", relates to a system in which one pair of contacts is spring-biased and another pair of contacts is through the spring.
Other patents on swiveling electrical connections for hand-held appliances are U.S. Pat. Nos. 3,950,052; 4,003,616 and 3,957,331.